An early heat wave resulted in people looking for relief from the heat by heading to local waterways. Due to the time of year, creeks and rivers were running cold, high and fast due to the winter rains and snowmelt.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS STO wrote it up.
An early heat wave resulted in people looking for relief from the heat by heading to local waterways. Due to the time of year, creeks and rivers were running cold, high and fast due to the winter rains and snowmelt.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Sacramento, CA wrote its last area forecast discussion before the first event at Apr 21, 8:55 PM PST, 3 hours 5 minutes earlier.
Area Forecast Discussion National Weather Service Sacramento CA 955 PM PDT Sat Apr 21 2018 .SYNOPSIS... Dry and warm through early next week. Chance of a few showers or thunderstorms over the mountains by mid to late next week. && .DISCUSSION... UPDATE: Isolated storm occurred Sat afternoon near the Crest in Tuolumne/Alpine Co, and for Sun/Mon the instability is forecast to shift a little Swd, although still slightly negative LI's are forecast in the Yosemite NP area. Then, the coverage should become more widespread over the Sierra from Tue through the middle of the week as the upper low approaches the CA coast. Temperatures are running a little warmer today than yesterday and should top out in the low to mid 80s throughout the valley. A weak dry trough will pass over the northern end of the state Sunday morning and weak north flow will develop behind the system. (UPDATE: Temperatures are expected to warm a couple of degrees on Sun compared to Sat's highs over areas generally S of I-80, but cool over areas to the north in the wake of the upper trof.) A ridge will stay over the area through the middle of next week as a low pressure system deepens off the coast and becomes cutoff from the jet. Temperatures will be running well above normal in the 10 to 15 degree range through Tuesday with the warmest days Tue/Wed. (UPDATE: Forecast max temps for RDD AP are running at record/near record levels for the 23rd to the 25th, 86 in 2002, 87 in 2013 and 90 in 2004, respectively.) Some moisture advects northward from the southwest over the Sierra nevada on Tuesday and may bring a few showers or even some isolated thunderstorms...mainly near the crest. && .EXTENDED DISCUSSION (Wednesday THROUGH Saturday) High pressure remains over the western US Wednesday and Thursday as a closed upper low sits over the eastern Pacific Ocean. Daytime temperatures will remain 5-15 degrees above normal through Thursday, and there's a slight chance of afternoon thunderstorms over the Sierra crest. Friday into the weekend, uncertainty is high as models diverge significantly on the speed and direction of the closed low movement. Generally, the upper low and associated surface cold front approaches the area on Friday, creating a chance for more widespread showers and afternoon thunderstorms over the Coastal Range and Sierra crests Friday through the weekend. Temperatures expected to cool down to near normal by Friday as the front passes through the area. HEC && .AVIATION... VFR conditions at the TAF sites the next 24 hours. Winds generally around 10 kts or less except vicinity Delta with winds 10-20 kts. && .STO WATCHES/WARNINGS/ADVISORIES... None. &&
1 cold/wind chill. Local standard time, as filed.
A 21 year old man drowned when he jumped off an embankment in Ripon on the Stanislaus River, he went under and water and didn't come up. The Stanislaus River, was running fast and cold from the winter rains and melting of snow in the mountains. His body was found by the Ripon Fire Department on May 10th.
As the offices recorded each death: direct deaths were caused by the weather itself, indirect ones by something it set in motion.
| Event | Date | Age | Sex | Where | Kind |
|---|---|---|---|---|---|
| Cold/Wind Chill, Southern Sacramento Valley | 2018-04-22 | 21 | Male | In Water | Indirect |
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2018Every state in 2018This day in weather historyWarnings in California, April 2018
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 761303.